The present invention relates to an improved method and apparatus for effectively winding a thread on a bobbin at a winding speed of more than 2500 m/min, whereby very smooth unwinding of the thread from the yarn package formed on the bobbin is facilitated.
In the textile industry such as the synthetic fiber manufacturing industry, it is the recent tendency that a non-drawn synthetic thread delivered from a spinning process or a drawn thread delivered from a spin-draw process is taken up at a high takeup speed of more than 2500 m/min, by the high speed running of a takeup device, so as to form a yarn package on a bobbin.
According to our experience, when the revolutions per minute of the bobbin during the winding (or takeup) process have some integral whole number relationship to the traverse rate, it may be seen the pattern or yarn placed on the yarn package is repeated. This pattern or yarn winding is well-known as "ribboning". When such "ribboning" is created during the winding operation of a synthetic filament on a bobbin, the thread layer formed on an axial end portion of the yarn package has a tendency to slide toward the axial middle portion of the yarn package. When such slip of the thread layer occurs, the thread is normally broken so that the desired full yarn package can not be produced. Even though the thread is not broken, the slipped thread layer creates an entanglement of thread when the thread is unwound from the yarn package in the subsequent process, so that the subsequent process can not be carried out in a stable condition and a good quality product can not be produced. Such defective yarn winding is frequently created in the winding (or takeup) operation under a condition of high speed winding. In the case of winding synthetic thread treated with an oiling agent having low frictional resistance, the above-mentioned defective yarn winding tends to frequently occur.